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arXiv · 2410.03206

A simple method to find temporal overlap between THz and X-ray pulses using X-ray-induced carrier dynamics in semiconductors

Yuya Kubota·Takeshi Suzuki·Shigeki Owada·Kenji Tamasaku·Hitoshi Osawa·Tadashi Togashi·Kozo Okazaki·Makina Yabashi
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Abstract

X-ray-induced carrier dynamics in silicon and gallium arsenide were investigated through intensity variations of transmitted terahertz (THz) pulses in the pico to microsecond time scale with X-ray free-electron laser and synchrotron radiation. We observed a steep reduction in THz transmission with a picosecond scale due to the X-ray-induced carrier generation, followed by a recovery on a nano to microsecond scale caused by the recombination of carriers. The rapid response in the former process is applicable to a direct determination of temporal overlap between THz and X-ray pulses for THz pump-X-ray probe experiments with an accuracy of a few picoseconds.

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Yuya Kubota, Takeshi Suzuki, Shigeki Owada, Kenji Tamasaku, Hitoshi Osawa, Tadashi Togashi, Kozo Okazaki, Makina Yabashi. 2024-10-04. A simple method to find temporal overlap between THz and X-ray pulses using X-ray-induced carrier dynamics in semiconductors. https://doi.org/10.1063/5.0242393

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